GMC Jimmy Brake and ABS Problems

spazjackson

can anyone tell me how to remove th power booster from my 1994 gmc jimmy...i do not know how to disconnect the rod from the break padel..
I have removed three of the four bolts from the inside..Do i have to remove the steering colum to
get to the top right bolt because i cant get to it from this angle...

omega7441

Hey all,

I was thinking about buying my in-laws Jimmy (not sure of the year atm). But I took it for a test spin and the brakes are horrible with it.

After getting it up to about 70 on the interstate, I literally stood on the brakes and it didn't do anything.... Eventually you will slow down and come to a stop, but you really gota have some muscle to get this thing stopped.

Now I need to know what to check for this, air in the lines? or anyting specific to this issue. I dont really want my wife and future child in this vehicle, but I would really like for them to have something like this to travel in.

Let me know,

Thanks
Nick

pcgeek

I have a 92 Jimmy SLT 4X4 w/ABS. I blew a brake line, to the rear, and now I cannot bleed the system correctly.
The peddle stays mushy and the dash lite stays on.
Does the ABS controller have to be reset or bled? If so, how?
The brakes do work, without activating the ABS, but the peddle travels most of the way to the floor.
The park brake is all the way up.

:sick:

jonina

I have had 2 new brake boosters and 2 new master cylinders put in and I still have the same problem. Spongy brakes, that sometimes go to the floor. They also feel like they are really hard sometimes.....like not power brakes at all. This problem has been ongoing for over a year and I have had about 10 different guys look at the truck. Nobody can seem to fix it and it scares the crap out of me. If you slam on the brakes the car does not stop quickly....it kind of lurches to a stop. I still drive it but always slowly to allow extra room for stopping.
The truck does have after market parts in it and I have even taken it to a GMC dealership to get their opinion and they also told me to replace the master cylinder and booster for 2500 dollars. I have already spent close to 1500 trying to fix this and I just don't want to spend 2500 to still have it not fixed!
This has been an ongoing nightmare and I just want to either fix this or get rid of this horrible truck....but i feel too guilty selling a car like this to anyone....it isn't safe.
Please help if anyone has any ideas....it has had all the lines bled. It has every other new brake part you can possible have.....it is just still weird. One guy told me it could be the something to do with the ABS but the dealership guy said that it wasn't that.

vikingsfan1

i keep getting carbon in my power brake booster and when this happens it starts to run rough how can i fix this problem

findlaydawg

I recently replaced both back brake calipers. I bleed both rear brakes. But i still had no brake pedal. I then bleed the front brakes and still no pedal. So i then bleed the master cylinder. I finally got a good stiff brake pedal. I started the vehicle and depressed the brake pedal and it went all the way to the floor and wouldnt pump up. Any suggestions?

lovechevyh8gmc

one of my brake pads on my rear driverside slid down from the caliper. the piston is fine and i was able to collapse it back down with a clamp when i put a new rotar and pads on. i drove back to my house from my dads and it smelled like hot metal i touched the rim and on the back two tires and they were hot to touch, the front were cool. the abs light was on on the way home and i was getting horrible mpg! any suggestions

fixnit247

I recently changed the front brake pads on my 97 jimmy slt 4x4,now the pedal is harder than ever to push down and i hear air pushing out from the brake pedal/powerbooster/firewall area. I have bleed the brakes also. This never happened until after i changed the pads. i dont think its the master cylinder because what are the odds of it going same day i do the pads. also when i push the pedal down the trucks idle will drop and sometimes stall out.. someone help!!!!

dbillz08

my ABS light has been on for a while. within the last few months, I have noticed that when it rains or my vehicle gets wet, the ABS brakes go activate when I am under 10 MPH...usually when coming to a stop. I have checked the wheel sensors and they are clean and don't seem to be wore out or anything. I am running out of things to check and was wondering if anyone could possibly diagnose this problem?

cutchant

If you still have a light on on the dash the equalizer valve is not centered measing you have a diffence in pressure start bleading from the furthest point from the master working to the master (right rear, left rear, right front, left front then bleed the master) also rember pedal hight come from the rear brakes if drum in rear check ajustment if disk check e-brake ajustment at the caliper may need to ratchet the piston in hope this helps

cutchant

check powert booster vacum supply also if you pull the masteraway slightly carfull not to kink the brake lines if their is fluid in the booster it is nogood also the master is leaking

tracyh68

If anyone knows the answer I have the same problem.

pabassman

i replace the rear brakes on my 2000 jimmy and left rear rotor and caliper now the pedal goes to the floor,i have no brakes in the rear and cannot drive the vehicl,i bled the brakes and noticed very liiitle fluid coming out after a few tries i got fluid but still no brakes can someone help!

squires21965

Just curious if u are still having the issue or what fixed it because I have the exact problem. Thanks Debbie

kevinpowell1

I have a 01 jimmy and the ABS light comes on and stays on for a few days and then turns off then comes back on... Any one know how to fix this problem???

mikebrangi

your caliper is no good ,
had the same issue with my s-10 the caliper's piston isnt releasing
may be able to free it up by cleaning the posts and the inner piston.
but the easiest thing to to is replace the caliper

johnbaum

I just replaced my Upper and Lower Ball Joints on both sides on my 98 Jimmy 4wd and a couple days later had an incident where after driving, stopped at the store. When I got back in the brake pedal went to the floor and I seemed to only have rear brakes. Thankfully, my trip was all uphill to get home so I wasn't too concerned but once I applied the brakes to turn, I once again had full pedal and the brake light went out. Initially I thought that I may have damaged a brake line during the ball joint change and that it was leaking but no leak and MC is full. I have heard of internal brake line failure but this usually causes the caliper to lock up. In the process of changing the ball joints, I did have to remove the Calipers from the Spindle and had to slightly compress the calipers to remove them but once pumped up they seemed ok until this happened. Could this be a MC or Proportioning Valve problem? I live in WV Mountains so brakes and good ones are important.

winsor6

I had the same problem with my 2000 Jimmy. The ABS sensor was bad in the left hub. Had hub replaced (the sensor is part of the hub assembly and can't be individually replaced. Now everything works fine.

bigrigger1

i have the same problem on my 2005 jimmy replaced master cylinder brake booster and abs module called the dealer it has to go in and put on a computer scanner to get ur brakes back

bigrigger1

no u dont have to remove the steering colume u can get a 3/8th ratchet and a 15 mm deep socket in behind the steel bracket have sum one pulling on brake booster while u turn nut off

bigrigger1

there is just a metal clip on ur push rod little flat screw driver wedge it in and pry out clip should fall out as it is slotted then remove the plastic brake lite actuator

bigrigger1

i would say sum one dis connected the vacuum line to ur power booster to compinsate for no brake pedal when running it doesnt solve ur brake problem any so id say take it in get it on scanner hook ur vacuum line back up should b gud to go

los2

left brake lights just went out. turn signals work. replaced both bulbs. checked harness at assembly, no break in wires. Any ideas? thanks